I was trying to look at what came up when searching for an ADC. I put in some requirements (see http://parts.io/search/Class-AD%2FDA%20Converters/Category-Analog%20to%20Digital%20Converter%20IC?Price=0-8.625&Sample%20Rate=99.00001-130&Number%20of%20Bits=10-16 ), and only two parts came up.
The parts are classified/described as an ADC (see http://parts.io/detail/1434368/LTC6401CUD-14%23PBF) on the Parts.io search along with the detailed page.
The 6400/6401 are actually ADC drivers (i.e. amplifier/buffer), not ADCs.
I will have @abrown take a look at this. Thanks for letting us know!
I have confirmed this series should be classified as a Differential Amplifier. We have submitted this to be corrected.